(function(){
	shuffle = function(array) {
		var i = array.length;
		while(i){
			var j = Math.floor(Math.random()*i);
			var t = array[--i];
			array[i] = array[j];
			array[j] = t;
		}
		return array;
	}
	
	var htmls = [];
	if (htmls.length < 1) return;
	document.getElementById('ad-zone-20').innerHTML = shuffle(htmls).slice(0, 1).join('');
})();